66887389 has 4 divisors (see below), whose sum is σ = 66927424. Its totient is φ = 66847356.

The previous prime is 66887363. The next prime is 66887399. The reversal of 66887389 is 98378866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66887389 - 2²¹ = 64790237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66887309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17397 + ... + 20890.

It is an arithmetic number, because the mean of its divisors is an integer number (16731856).

Almost surely, 2^66887389 is an apocalyptic number.

It is an amenable number.

66887389 is a deficient number, since it is larger than the sum of its proper divisors (40035).

66887389 is a wasteful number, since it uses less digits than its factorization.

66887389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40034.

The product of its digits is 3483648, while the sum is 55.

The square root of 66887389 is about 8178.4710673817. The cubic root of 66887389 is about 405.9271326920.

It can be divided in two parts, 66887 and 389, that added together give a palindrome (67276).

The spelling of 66887389 in words is "sixty-six million, eight hundred eighty-seven thousand, three hundred eighty-nine".